Physical vs. Chemical Changes

Learning Scale 4 – Design an experiment to determine the identity of an unknown using its physical and chemical properties. 3 – Differentiate between physical and chemical changes. Explain how mass is conserved during physical and chemical changes 2 – With help, I can describe examples of physical and chemical changes. Describe how temperature influences chemical changes. 1 – Define physical and chemical change.

The Law of Conservation of Mass Mass is conserved (not created or destroyed) when substances undergo chemical changes.

Physical Change Anytime you alter a substance but it is still the same substance.

Indicators of a Physical Change Expected Color Change Mixing Change in Shape Phase Change Change in Size

Chemical Change When something undergoes a chemical change and forms a new substance.

Indicators of a Chemical Change Fire Change in Energy – heat, light, sound Production of a Gas Unexpected Color Change Precipitate

Physical Change Key Words Chemical Change Key Words Twisted Bent Crushed Froze Boiled Melted Condensed Dissolved Expected Color Change Burned Flammable Fire Combusted Cooked Fizzed / bubbled Unexpected Color Change Decomposed

Is this a physical or chemical change? Why?

Is this a physical or chemical change? A new substance forms

Is this a physical or chemical change? Why?

Is this a physical or chemical change? Still the same substance

Think Pair Share How can you differentiate between physical and chemical changes?

Learning Scale 4 – Design an experiment to determine the identity of an unknown using its physical and chemical properties. 3 – Differentiate between physical and chemical changes. Explain how mass is conserved during physical and chemical changes 2 – With help, I can describe examples of physical and chemical changes. Describe how temperature influences chemical changes. 1 – Define physical and chemical change.